$(function() {
	var lunbotu = new Swiper(".kv_box", {
		autoplay: 1500,
		loop: true,
		pagination: '.swiper-pagination',
		prevButton: '.swiper-button-prev',
		nextButton: '.swiper-button-next',
	});

	$(".back_top").on("click", function() {
		$("body").animate({
			scrollTop: 0
		}, 200)
	})
	var backTop = document.querySelector(".back_top");
	backTop.addEventListener("click", function() {
		document.documentElement.scrollTop = document.body.scrollTop = 0;
	})
})